You're making a mistake in not looking at the substance of what people have said and are saying, and collapsing several very different episodes into "every time facebook makes a change". Reactions to Facebook changes, and results, have actually been quite different.
The first big outcry was about the introduction of newsfeeds. People were upset because Facebook sprang it on them by surprise, and suddenly information was being shared in new ways that people weren't used to, hadn't expected, and had no control over. In the long run, newsfeeds turned out to be one of Facebook's most useful and visionary features, but they did make two mistakes:
1. Surprising people, causing them to realize after the fact that they'd shared information in ways they hadn't intended
2. Providing no control. Facebook's success owes a lot to the way it offers people very granular control over their privacy and sharing.
Facebook fixed #2 by adding granular privacy controls for newsfeeds, and #1 just naturally fixed itself once people figured out the new system.
A couple of later episodes of "everyone whines" were different: Facebook made a big mistake, everyone complained, and Facebook backed down completely, thus quieting the criticism:
1. "Beacon", which let partners' web sites post to people's feeds (for example, you buy a book at Amazon and it appears on your feed). Facebook pulled Beacon. They later began reintroducing some of the more useful aspects of Beacon in limited ways, with better user control, and this has been useful.
2. The change to Terms of Service a few months ago. Huge outcry, Facebook admitted their error, backed out the changes, and started work on a new terms of service to fix problems in public view with public comment.
Another case, and probably the one you're thinking of, was last year's profile redesign. That time, Facebook did things right: They informed people early, and opened a group where they posted weekly mock-ups of what they were thinking and asked for comments in a managed way, and responded to the previous week's comments. The process went for several months, and I followed it and could see how it improved the design significantly.
When the new design came out, some people did indeed object vocally. But a lot of other people (me included) saw the value of it because we'd been included during the design process, and because the new design really did have a lot of advantages, which we could articulate. This outcry took a different path than previous ones: Facebook did not have to make any changes, and instead, proponents of the new design eventually converted most of the opponents.
When Pages were overhauled recently in the same way as the Profile redesign from last year, there was no major outcry.
And now we come to this new Facebook redesign: It really is AWFUL. They threw away all that they learned last time. They took out most of the advantages of last year's redesign, eliminated many of the most useful features, and actually went back even further, effectively eliminating the newsfeed. They did not include users in the redesign process, and they did not give previews or warning.
Your analysis is much too simplistic, and misses almost everything significant about the differences between these episodes of Facebook changes followed by objections from users, and therefore misses all of the factors that make each episode different from some of the others.
While its true that Facebook users always bitch and moan about changes. This time they're bitchin' and moanin' annnddd using a very key word: confusing.
I fail to see why A) Web developers need to put down their users constantly, instead of working with them. B) Why web developers think that Twitter can do no wrong.
The elitist holier-than-thou web developer herd mentality is mind-boggling.
It would seem people are just perpetually afraid of any sort of change at all